Create 26 September Rotate Deque By K (#897)

Author: Chayandas07

26 September Rotate Deque By K

@@ -0,0 +1,20 @@
+class Solution {
+  public:
+    void rotateDeque(deque<int>& dq, int type, int k) {
+        int n = dq.size();
+        if (n == 0) return;
+
+        k %= n; // no need to rotate more than n times
+        if (k == 0) return;
+
+        if (type == 1) {
+            // Right rotation: move last k elements to front
+            rotate(dq.begin(), dq.end() - k, dq.end());
+        } 
+        else if (type == 2) {
+            // Left rotation: move first k elements to back
+            rotate(dq.begin(), dq.begin() + k, dq.end());
+        }
+    }
+};
+